Issue #3314247 by joelpittet: TypeError: in_array(): Argument #2 ($haystack) must be of type array

field_group.features.inc

@@ -31,7 +31,9 @@ function field_group_features_export_alter(&$export, $module_name) {
       list($entity_type, $bundle, $field_name) = explode('-', $field);
 
       foreach ($field_groups as $group_id => $group) {
-
+        if (!isset($group->data['children'])) {
+          continue;
+        }
         if ($group->entity_type == $entity_type && $group->bundle == $bundle && in_array($field_name, $group->data['children']) && !in_array($group->identifier, $export['features']['field_group'])) {
           if (isset($group->export_module) && $group->export_module != $module_name) {
             $export['dependencies'][$group->export_module] = $group->export_module;